The lifetime prevalence of major depressive disorder is ∼16.5% and, each year, ∼800 000 individuals worldwide die as a result of suicide, a high proportion of whom suffered from severe depression. Even with treatment, 20% of patients experience chronic symptoms, meaning that major depressive disorder accounts for a greater number of years lived with disability than any other illness. A combination of genetic susceptibility, chronic stress and developmental factors predispose to depression by triggering alterations in neuroplasticity, biochemistry, and brain structure. As illustrated by a recent meta-analysis, structural brain changes predominantly affect the lateral ventricles, basal ganglia, thalamus, hippocampus and frontal lobes (Kempton et al., 2011). In this issue of Brain, Maller et al. (2014) reveal that structural changes also extend to the occipital lobes, with ‘occipital bending’—in which one occipital lobe wraps around the other—three times more prevalent in patients with treatment-resistant major depressive disorder than in healthy controls.

Bending or asymmetry of the occipital cortex has not been examined in major depressive disorder before. However, it is worth noting that although the occipital cortex is not among the core regions that exhibit structural changes in major depression, alterations in biochemistry, white matter structure, resting state connectivity and grey matter volume have previously been reported in the occipital lobes in this disorder (Bhagwagar et al., 2007 …